1. Field of the Invention
The present invention relates to a process for the production of fine structures on a base such as electrode patterns or conductor patterns on a semiconducting device which method includes utilizing an etch-resistant mask and etching a portion of the base which is exposed by the mask.
2. Prior Art
Processes for forming conductor patterns by applying an etch-resistant mask on a layer of conductor material and then etching away portions of the layer of conducting material to provide conductor paths are known. Such processes are employed in the production of highly integrated semiconductor circuits with fine structures in the order of 1 .mu.m. It is a known fact that in these circuits, the etching of the individual layers presents one of the greatest problems. These problems lead to a lateral under-etching beneath the edges of the etching mask which usually consists of a photo-resist and thus to a loss of dimensions in comparison to the etching mask structure. The under-etching is approximately equal to the thickness of the conductive layers such as aluminum layer which is to be etched. Other disadvantages of the process are based on the fact that the slopes of the etched conductor path structure at its upper part are generally vertical and that the edges of the conductor paths are generally jagged.
Ion etching processes do not have the above-mentioned disadvantages of the known processes. However, they do involve a series of other problems such as damage to the semiconductor surface or a difficulty in removing the photo-lacquer after the etching process.